Under the Bathing Water Directive, bacteriological water quality at Scarborough South Bay was classified as poor in 2016. This was unexpected following significant investment by Yorkshire Water in 2014 to improve bathing water quality.

In response to the result, investigations by Yorkshire Water and the Environment Agency have established that the discharge from the outfall at Wheatcroft could have more impact on water quality than had been previously thought. In addition it has become clear that there may be a number of other sources of bacteria impacting on the bathing water quality which is known to be impacted by occasional high peaks in bacterial contamination.

This investigation sought to establish any similarities and relationships between the bacteria present in a number of identified potential sources around Scarborough Bay and the bacteria found at the bathing water at Scarborough South.

A number of techniques were employed looking at the origins and characteristics of the bacteria found in samples of various sources and receptors taken during the summer of 2016.

The key conclusions are:

The final effluent discharging from the Wheatcroft outfall contains high numbers of bacteria and that these were found on occasion, but not consistently, in the bathing water at Scarborough South.

There is a strong indication that sea bird faeces is likely to be contributing to overall bacterial contamination of the bathing water at Scarborough South.

A marker associated with human pollution was consistently detected in the bathing water at Scarborough South.

A marker associated with dogs was found in 2 of the samples taken from Scarborough South.

None of the samples taken from either Scarborough South or North Bays contained markers associated with ruminant animals (cows/sheep)."